Tractor



A. N. CALKINS June 8 19 26.

TRACTOR Filed March 25 1925 2 sheets sheet 1 June 8 1926. 1,587,756

A. N. CALKINS TRACTOR Filed March 25, 1925 v 2 Sheets-Sheet 2 PatentedJune 8, 1926.

UNITED STATES annrson n. ca tains, or comer, mmno rs, nssrenoa ToELECTRIC wanna com a conrona'rron or mentors.

rm, QUINCY, I'LLINOIS,

issues PATENT crates.

TRACTOR.

Applicatlon flled March 25, 1925. Serial m. races.

The invention relates to tractors of the ty-p'e comprising, incombination with spaced rotary supporting inembers,'an endless chaincomposed of separate sections or links coacting to i'estrainfieiring inan upward direction as the chain travels over the ground, but

permitting a bending or flexing of the chain aroundthe supportingmembers.

The object of the invention generally stated is to produce a chain forsuch a tractor in which the link sections are operatively connectedtogether in a novel and advantageous'manner to produce between adjacentlinks a truss action operating to prevent flexing of the chain upwardlyas it passes over the ground, but permitting relative pivotal movementbetween the sections. as

the chain passes around the supporting members. I A general object. isto produce a chain having a link section of 'simplc construction, orrelatively light weight capable'ot withstanding long and severe usage,and capable of manufacture on an economical basis.

In the accompanying drawings there is shown'a preferred embodiment ofthe invention, but it will be understood that various changes in theconstruction and arrangement set forth are contemplatedwithin the scopeof the invention as expressed in the ap nded claims.

igure 1 of the drawings is a fragmentary side elevational view of theimproved trac tor with the axle of one of the supporting M membersinsection.

Fig. 2 is a fragmentary horizontal section taken a roxim'ately in theplane of line 2.2 of Fig. 1.

Fig. 3 is a in M showing gather.

Fig.4 is an end view of the same. Fig. 5 is a fragments? verticalsectional 'view taken a proximatey in the plane of line 5-5 of ig. 3. I

Fig. 6 is a transverse-section taken in the plane of line 6-45 of Fig.5. p 4

Fig. 7 is 11. pers tive view of the major portion of onelin section.Fig. 8 is apers ctive view showing another portion of th link section.The tractor com rises generally a central frame member 10 e ongatedinform andprovidi ng bearinigs, at o posits ends in which 55 arejou'rnalleth two li sections connected toentary inner plan view rotarysupportingmembers or wheels 12.

The frame member is mounted. substantial lv%idway between its endstoturn on a she 13 upon which the tractor frame proper is supported in theusual way.

The endless belt or chain is composed of a pluralityof similar sectionseach compris ing a tread portion or shoe 14 generally rectangular inform with its greatest dimension extending laterally of the'iractor.Rising from this shoe approximately centrally thereof is an upstandingstructure prefer ablyformed integral with the shoe and (mill prising twopairs of arms 15 and 16 terminating at their inner ends in a erallyspaced bearings 17 adapted to. support hit a pivot bolt 18 a substantialdistance above the shoe and approximately in the median planethereof.The outer endsof the arms 15 are formed integral with a bearir at theforward edge of the shoe 14 am diverge slightly while incliningrearwardly and u wardly for connection with the hear ings 1 The outerends of the arms 16 are formed integral with late-rally s aced bearings20 at the rear edge of the nection at such ends with the bearings 1?.

At opposite side edgesbf the shoe are formed I 0e 14 and-converge,toward their inner ends for contilt " alined with thebearing=19 these tree port tion's be'ntg' preferably cored out asindicated) at 23 (Fig. 7 to lessen the weight of they.

section. Suitable reinforcing ribs 24 may he provided on the inner faceof the shoe as clearly indicated in Fig. 7;

The arrangement of. he parts is such that the laterally spaced bearings2d at the rear or trailing edge of the shoe are adapted to enter betweenthe intermediatehearing 119 .andalined bearings 22 at the forward edgeof the next adjacent shoe, the two sections being pivotally connectedtogether by a piv it 0t pin '25 passing through the several ahned bearinpin 25 in place the bearings 22 have formed at their outer ends a pairof lugs 26 on lugs are aperturedto receive a retaining 19, 2 0 and 22.To'hold the. pivot o posi te sides of the bearing aperture, whic h eaxes 11 of two pairsloi tions areop'eratively connected in a manner mlsuch relative pivotal movement j between the tread portions in onedirection, but to pmvent relative pivotal movement between' the sections1n the opposite direction as the chain travels over V e ground. For

thus connecting the inner end portions of the link sectionstogether eachis provided with a tie-member28 having one enclrigidly se beyond thcured near the inner ends of the arms 15 and lfiand its other endextended forwardly e link section for-pivotal and sliding cdnnectionwith the inner end portion of the'next adjacent link section. For con--venienoe in manufacture,- and in order that it may readily be replacedor renewed, I prefer tomalte each of the members 28 in the form of aseparate casting. Asherein shown it comprises anarm 29 having at itsrear end a yokeportion'30 adapted to straddie the Spaced beari 17 and,having side portionswith vertica y spaced-apertures 31 "and 32. a Theapertures 31 are adapted to a link section, as shown clearly in- Fig. 5.The

1 arm preferabl curves outwardly slightl ,the 5 arrangement in such thatin the re ative pivotal movement tween adjacent link, sections, as thelatter pass around the'rotary'.

5e T the side 11 for one pair of su I the la permitted 'b-v the movementof ed so thetrack 'elidable in, a bearing 7 x 3 9- at one en supportsthe heads 35 ma pass through the yo cs 30 of the next' jacent sectionsasthe pivot bolts 18 the slots 36; I i

To guide the 1' "sections around the rotary supportinglmemberam thetrack .portions 21 of cat: inward] extending flanges 3 aft the inner {Yportions; and to cause the 'li I sections to adhere snugly to theperiphcries of the supporting members as they pass around them, means isprovided'operating to maintain the chain under tension. Thusorting'mem'" here 12 'i'sniounted'm a moviiiiie bearin 3% o v the framemember 10. The latter has an opening 40; therein at. one end of which ismounted a screw tl having an adjusting nut 42 thereon between fwhiph andthe bearing'38' is interposed a coiled expansion spring 43, r axingthrough a suitable opening in one si eof thcbearmg. box.

It will be seen that by' the construction provided a rigid tread ofsuhetantial length s in effect produced as the chain travels overnegro-rind, which tread is flexiblein the o poaite direction to permitthe passage of t e .ment between the.

7 section are rovided with at thelr leading and ,trailingedgles t chainaround its rotary supports; In supporting theload the adjacent linksections The chainthus possessesg'reat strength and the construction issuch that-the parts are subjected to very little wear. In thisconnection it will be noted that the arcuatc'slot 36 in the head 35 ismadeof a width-throughout the major portion ofits length slightlygreater'than the diameter of' the pivot-bolt 18 so as to avoidv frictionbetween t-hese 'parts,

I claim as my invention:

1.'A tractor of-the character.described .comprising an endless chainhavinga series of link sections each including'a tread portion, meanspivotally connecting the tread portions in edge to edge relation, aninwardextending structure rigid with each of said tread portions andhaving a pivot-mounted therein near its inner end substantially in themedian plane of the tread portion with a part having one end in the formof'a yoke mounted on'said pivot and its other end-interfitting with theyoked end of thenext ad jacent part and having an elongated-openingtherein adap'ted'to receive the pivot of the next adjacent sect-ion, thearran e'ment being such that said parts coact with t e piv-- ot bolts torestrain relative pivotal move-f ment betweent'he' sections in onedirection but permit a limitedrela-tive pivotal movcdirection.

2. A'tract'or having an endless chain comsections in the opposite edgestoward, the median, lane of the tread portion, a connecting mem er rigidwiththe inner bnd'sof said arms and extending forwardly therefrom, saidmemberhaving an elongated opening iri its forward end, and

connecting vme'mberof the next adjacent link section is adapted to en apivot bolt carried-by'the inner ends of said arms with which the slottedend of the '3. A tractor havmg'an en ess chainco'mposed ofa series oflink sections comprising tread ortions pivotally connected togetheraplurality of arms formed integra wit portion of each section andextending inwardly from itsforward and rear-edges toward'the medianplane of the tree poret'readtion, a member rigid with the inner"ends.- 2

of said arms and extending "forwardly therefrom,saidmember having anelongated opening in its forwardend and a pivot bolt l carried bythefinner-ends of said arms with which'the slotted end of the connectedmem- 01%? the next aljac-snt iii-1k sectimi is adapted to engage,COHDQCUHQE' member baing farmed sepmat aly imm said mms 55 ml series 0??link sect-ions with tread pmtisns pimt-afly cozinecte iogethar meanssuppm'ia pair of spaet bearings immrcfiy 0f tread poytion of ,each-seti0n LPKH'OLlmateiy centrally 0f the reai poriian, pivm mbimted insaid bearings, a wnzlecting member mounvied 0n saiii pivot bolt and exmniing forwardly for pivetal and sliding -ummecti0n with the pivot bolt ofthe next adjacent section, and mans opemting $0 1510 161; saidconnectingmember against hum-- u on its supporting pivot,

n A tracts ofwia character dw eri'bedi' plurality of link 93060115; hawtrend portions piw'mally conmeiaed. m r and. @3611 having a; of Mammfiybearings mounted inwarflly'sf tha 'i read'poriien substazntiafiy mmbmliythere of, a pi'vst bait married by mic}, beaxings, a. membar having oneand. in mm farm 01?? a yeke mounted m the pi'wib 001$ 0i? me A.) Mu"Luisa and ada gw l t0 straddifi said spaced b: mugs and its ethsl' andadapted to enter. bei vex thespafie bmim's of the adjmmt- 665M011 havingfinngmed opening in zzzapimld 1x. recei -m the phat-700.1%

cmnmising plgrzzfity of iink'sactiom him; giurtians piwwfiy mmemmd m"mmi" and well haying a Q1 fimwmly 331i bearings .mfiuinted; immri ly s1?$3 262 wad. pmiim substammfi caml'alliy mm" @11 a pimis bolt ism-viedsaid bmwings 5L membar haying (me enfi mommeqi on we imit bflt @f wesegzfim mmflfiwmgher receive thefiwot bolt 01? said ad'jhcgmt tion saidmember baing 118M against mt? tinn 0n i'iza'supporting pivmfi bQHL'ther-wi, a pivpafi camied by said. hemimgy and a member having 0m @1161mounteci on. ai pivot and ibs uther and (m thapwet 0?? the adjacealtsction, (sine and of saii m L bay bemg slatted t0 reeewe lts pwut zmdiibhe othmr @ngl being in. the .iform 0E a yelma s0 stradfile gent membw.

8. A. tic-amino? M the cmmcwr comprising an fimdless'chain c ampamd @iia, series 03% fink swfiions wiizh maad. prslgjfiigns pivmmliy "cnnneatedmgathmg ampperiling pair 01? spasm hearimgs imwamily slotted emi (If themm; 4

'slimiing connectien withthe pivot bo lfi 9f the mxgmdjacem se-ciml,and; means operating- 7% hold Saki mmmciuing member a ainst turning onsupportng pivm, 'piv-' 0m zmdi sliding w mectien mci'udigg 21 Elm;

in midi smmwctim member at m widfi-h throughomfi tm mama partisan at 31%Eengbh slight} gnaw? mm @m diamaearwsr @115 the pimt 01%;

Nmmma 'in testimnny whamufi, I hams hewmm sai

